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1.
Heliyon ; 10(11): e32339, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38961949

ABSTRACT

Methyl orange (MO) is a dye commonly used in the textile industry that harms aquatic life, soil and human health due to its potential as an environmental pollutant. The present study describes the dye degradation ability of Serratia marcescens strain ED1 isolated from textile effluent and characterized by 16S rRNA gene sequence analysis. The laccase property of bacterial isolate was confirmed qualitatively. The effects of various factors (pH, temperature, incubation time, and dye concentration) were evaluated using Response Surface Methodology (RSM). The maximum dye (MO) degradation was 81.02 % achieved at 37 °C temperature and 7.0 pH with 200 mg/L dye concentration after 48 h of incubation. The beef extract, ammonium nitrate and fructose supplementation showed better response during bioremediation among the different carbon and nitrogen sources. The degree of pathogenicity was confirmed through the simple plate-based method, and an antibiotic resistance profile was used to check the low-risk rate of antibiotic resistance. However, the fate and extinct of degraded MO products were analysed through UV-Vis spectroscopy, FT-IR, and GC-MS analysis to confirm the biodegradation potential of the bacterial strain ED1 and intermediate metabolites were identified to propose metabolic pathway. The phytotoxicity study on Vigna radiata L. seeds confirmed nontoxic effect of degraded MO metabolites and indicates promising degradation potential of S. marcescens strain ED1 to successfully remediate MO dye ecologically sustainably.

2.
Exp Cell Res ; 439(1): 114092, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38754617

ABSTRACT

Asymmetric stem cell divisions play instrumental roles in the maintenance, growth and differentiation of organs. Failure of asymmetric stem cell divisions may result in an array of developmental disorders, including cancer. It is well established that the gene, inscuteable, acts as the upstream component of asymmetric cell divisions. In Drosophila larval midgut, a founder adult midgut precursor (AMP) experiences an asymmetric division to instruct its first daughter to become a peripheral cell that serves as a niche where the AMP and its future daughters can remain undifferentiated. The present study demonstrates that inscuteable expressing stem cells require Rab11, a conserved small Ras-like GTPase, for proper proliferation and differentiation. As insc-GAL4 mediated Rab11RNAi in Drosophila larval and adult midguts show the disruption of the niche microenvironment of adult midgut precursors as well as elevated DPP signalling at the larval stage, which is associated with aberrant over-proliferation and early differentiation of larval AMPs and adult intestinal stem cells. The observed connections between Rab11, larval AMP proliferation, niche establishment, and DPP signalling highlight the potential for Rab11 to serve as a key regulatory factor in maintaining tissue homeostasis and balanced cellular growth.


Subject(s)
Cell Differentiation , Drosophila Proteins , Larva , Signal Transduction , rab GTP-Binding Proteins , Animals , Cell Differentiation/genetics , Drosophila Proteins/metabolism , Drosophila Proteins/genetics , rab GTP-Binding Proteins/metabolism , rab GTP-Binding Proteins/genetics , Larva/growth & development , Larva/metabolism , Larva/genetics , Cell Proliferation , Stem Cells/metabolism , Stem Cells/cytology , Drosophila melanogaster/metabolism , Drosophila melanogaster/genetics , Drosophila melanogaster/growth & development , Stem Cell Niche
3.
Cureus ; 16(3): e55529, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38576659

ABSTRACT

BACKGROUND: Effective pain assessment is crucial to tailor the analgesic regimen post-operatively. Perfusion index (PI) has been reported to be a useful objective assessment tool for monitoring pain. This study aimed to explore the utility of PI in assessing postoperative pain in upper limb surgeries under supraclavicular block and its correlation with visual analogue scale (VAS) scores. METHODS: This prospective, observational study included 140 patients scheduled for elective upper limb surgeries. PI, VAS scores, heart rate (HR), mean arterial pressure (MAP) and physiological parameters were recorded at baseline and postoperatively. Inj. tramadol was administered when the VAS score exceeded ≥ 4 and the VAS score, PI, HR and MAP were recorded at 5, 10, 15 and 20 minutes after administration. Comparison of normally and non-normally distributed data was done using t-statistics and Mann-Whitney U-test respectively. Pearson correlation was used to establish a correlation between variables and the receiver operating characteristic (ROC) curve was used to calculate the cut-off value of PI to determine the onset of pain. RESULTS: There was a significant and moderate correlation between pre-analgesic and post-analgesic PI and VAS score (r = -0.425 and -0.448 respectively, p<0.001), while PI and MAP or PI and HR showed only a weak correlation. A cut-off value of 14.7 for PI showed 76.3% sensitivity and 100% specificity in predicting rescue analgesia requirements. CONCLUSION: The study supports the use of PI as an objective measure for postoperative pain assessment, with a notable correlation with VAS scores. The identified cut-off value for PI adds to its clinical utility in predicting the need for rescue analgesia.

4.
J Org Chem ; 89(6): 3769-3780, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38442363

ABSTRACT

Eosin Y catalyzed syntheses of bioactive tetraketones using cyclic-1,3-diketones and tertiary amines as alkyl synthons under 18 W blue LED have been accomplished. The condition is very mild that uses air as a green oxidant and avoids previously used harsh conditions like high temperature. Diverse arrays of tertiary amines first undergo reductive quenching of excited photocatalysts to form iminium ions that upon subsequent attack by cyclic-1,3-diketones give rise to tetraketones. This method is demonstrated with 31 examples with yields up to 76%. The feasibility of this reaction in the presence of eosin Y catalyst under a solar condition is also demonstrated with significant examples.

5.
Exp Cell Res ; 435(2): 113953, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38278285

ABSTRACT

Drosophila geneticists frequently employ the binary GAL4-UAS system of conditional gene expression to direct expression of the desired transgene in tissues of interest. The inscuteable -GAL4 driver (insc-GAL4) expresses in the type 1 and type 2 neuroblasts of Drosophila larval brain, a frequent target tissue in many investigations. This GAL4 line additionally displayed its expression in the midgut. In this study, we examined the expression of the UAS-mCD8GFP reporter under the command of the insc-GAL4 driver and observed that this driver expresses exclusively to intestinal stem cells (ISCs) of the Drosophila adult midgut as well as adult midgut precursors (AMPs) of the larval midgut besides its expression in larval brain. Additionally, using the G-TRACE method, it was observed that AMPs in the larval midgut consistently expressed insc-GAL4 in real-time, and the lineage expression of this GAL4 was observed in the enterocyte cells. This study reveals for the first time that insc-GAL4 is specific to larval AMPs and adult ISCs of the midgut.


Subject(s)
Drosophila Proteins , Drosophila , Animals , Drosophila/metabolism , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Transgenes , Intestines , Brain/metabolism , Drosophila melanogaster/genetics , Drosophila melanogaster/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism
6.
J Complement Integr Med ; 21(1): 61-70, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38016708

ABSTRACT

OBJECTIVES: The invasive screening methods and the late stage diagnosis of colorectal carcinoma (CRC) are contributing for the devastative prognosis. The gradual shift of the disease pattern among younger generations requires the implementation of phytochemicals and traditional medicines. Arkeshwara rasa (AR) is a herb-mineral combination of Tamra bhasma/incinerated copper ashes and Dwigun Kajjali/mercury sulphide levigated with Calotropis procera leaf juice, Plumbago zeylanica root decoction and the decoction of three myrobalans (Terminalia chebula, Terminalia bellerica, Emblica Officinalis decoction)/Triphala decoction. METHODS: The SW-480 cell line was checked for the cytotoxicity and the cell viability criteria with MTT(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) assay. The acridine orange/ethidium bromide (AO/EtBr) assay revealed the depth of apoptosis affected cells in the fluorescent images. The FTIR analysis exhibited the graphical spectrum of functional groups within the compound AR. RESULTS: The IC50 from the 10-7 to 10-3 concentrations against SW-480 cells was 40.4 µg/mL. The staining of AO/EtBr was performed to visualize live and dead cells and it is evident from the result that number of apoptotic cells increases at increasing concentration of AR. The single bond with stretch vibrations of O-H and N-H are more concentrated in the 2,500-3,200 cm-1 and 3,700-4,000 cm-1 of the spectra whereas, the finger print region carries the O-H and S=O type peaks. CONCLUSIONS: The AR shows strong cyto-toxicity against the SW-480 cells by inducing apoptosis. It also modulates cellular metabolism with the involvement of functional groups which antagonizes the strong acids. Moreover, these effects need to be analyzed further based in the in vivo and various in vitro models.


Subject(s)
Apoptosis , Minerals , Preliminary Data , Cell Line , Minerals/pharmacology
7.
J Ayurveda Integr Med ; 15(1): 100823, 2024.
Article in English | MEDLINE | ID: mdl-38160612

ABSTRACT

BACKGROUND: The diverse specificity mode of cancer treatment targets and chemo resistance demands the necessity of drug entities which can address the devastating dynamicity of the disease. OBJECTIVES: To check the anti-tumour potential of traditional medicine rich in polyherbal components and metal nanoparticle namely Arkeshwara rasa (AR). MATERIAL METHODS: The AR was prepared in a modified version with reference from Rasaratna Samuchaya and characterized using sophisticated instrumental analysis including XRD, SEM-EDAX, TEM, TGA-DSC, and LC-MS and tested against the MDA-MB-231 cell line to screen cell viability and the cytotoxicity with MTT, SRB and the AO assay. RESULTS: XRD pattern shows cubic tetrahedrite structure with Sb, Cu, S peaks and trace elements like Fe, Mg, etc. The particle size of AR ranges between 20 and 30 nm. The TGA points thermal decomposition at 210 °C and the metal sulphide peaks in DSC. LC-MS analysis reveals the components of the formulation more on the flavonoid portion. The IC50 value of MTT and SRB are 25.28 µg/mL and 31.7 µg/mL respectively. The AO colorimeter substantiated the cell viability and the apoptosis figures of the same cell line. The AR exhibits cytotoxicity and reaffirms the apoptosis fraction with SRB assay. CONCLUSIONS: The Hesperidine, Neohesperidin, Rutin components in the phytochemical pool can synergize the anti-tumour potential with either influencing cellular pathways or decreasing chemo resistance to conventional treatment. AR need to be further experimented with reverse transcription, flow cytometry, western blotting, etc.

8.
Future Microbiol ; 18: 1235-1249, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37750761

ABSTRACT

Aim: To elucidate the antibacterial activity of Sida cordifolia L. phytoextract, evaluate its polyphenol profile and optimize conditions against certain common foodborne bacteria. Methods: After polarity-based sequential extraction, S. cordifolia phytoextracts were tested for antibacterial potential against antibiotic-resistant bacteria. Box-Behnken design was used to optimize several process parameters and ultra-performance liquid chromatography confirmed the phenolic composition of the best possible outcome. Results: Agar well diffusion and MIC/MBC assay confirmed a strong bactericidal effect of ethanolic (SC04-ET) extract against ampicillin and colistin-resistant Escherichia coli, Listeria monocytogenes and Staphylococcus aureus. The direct interactive effect of optimized conditions showed maximum antibacterial performance and ultra-performance liquid chromatography revealed a high amount of phenolic compounds. Conclusion: The results confirmed that ethanolic extract of S. cordifolia has potent bactericidal action against foodborne bacteria.


What is this article about? There are bacteria in food that can make people ill. These are usually treated with antibiotics but sometimes, these bacteria become less susceptible to the antibiotics. This article looks at a natural alternative to antibiotics that is tested against three types of bacteria linked to foodborne illness. What were the results? This study found that the plant extract, a natural extract derived from different parts of plants such as leaves, stems or roots, can kill bacteria that are resistant to antibiotics. What do the results of the study mean? This study suggests that the plant extract could be a natural and effective way to kill bacteria. This could be useful in the food and medicine industries.


Subject(s)
Listeria monocytogenes , Plant Extracts , Plant Extracts/pharmacology , Plant Extracts/chemistry , Microbial Sensitivity Tests , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Ethanol/pharmacology
9.
Chem Asian J ; 18(17): e202300510, 2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37541298

ABSTRACT

Development of probe systems that provide unique spectral signatures for duplex, G-quadruplex (GQ) and i-motif (iM) structures is very important to understand the relative propensity of a G-rich-C-rich promoter region to form these structures. Here, we devise a platform using a combination of two environment-sensitive nucleoside analogs namely, 5-fluorobenzofuran-modified 2'-deoxyuridine (FBF-dU) and 5-fluoro-2'-deoxyuridine (F-dU) to study the structures adopted by a promoter region of the c-Myc oncogene. FBF-dU serves as a dual-purpose probe containing a fluorescent and 19 F NMR label. When incorporated into the C-rich sequence, it reports the formation of different iMs via changes in its fluorescence properties and 19 F signal. F-dU incorporated into the G-rich ON reports the formation of a GQ structure whose 19 F signal is clearly different from the signals obtained for iMs. Rewardingly, the labeled ONs when mixed with respective complementary strands allows us to determine the relative population of different structures formed by the c-Myc promoter by the virtue of the probe's ability to produce distinct and resolved 19 F signatures for different structures. Our results indicate that at physiological pH and temperature the c-Myc promoter forms duplex, random coil and GQ structures, and does not form an iM. Whereas at acidic pH, the mixture largely forms iM and GQ structures. Taken together, our system will complement existing tools and provide unprecedented insights on the population equilibrium and dynamics of nucleic acid structures under different conditions.

10.
Article in English | MEDLINE | ID: mdl-37395874

ABSTRACT

The rising global cancer rate is driving up the consumption of anticancer drugs. This causing a noticeable increase in the levels of these drugs in wastewater. The drugs are not metabolized effectively by the human body, leading to their presence in human waste, as well as in the effluent from hospitals and drug manufacturing industries. Methotrexate is a commonly used drug for treating various types of cancer. Its complex organic structure makes it difficult to degrade using conventional methods. The present work proposed a non-thermal pencil plasma jet treatment for methotrexate degradation. The air plasma produced in this jet setup is electrical characterized and plasma species/radicals are identified using emission spectroscopy. The degradation of drug is monitored by studying the change in solution physiochemical properties, HPLC-UV analysis, and removal of total organic carbon, etc.Results show that a 9-min plasma treatment completely degraded the drug solution that followed first-order degradation kinetics with rate constant 0.38 min-1 and 84.54% mineralization was observed. Additionally, an increase in electrical conductivity and dissolved solids compared to virgin water-plasma interaction indicated the formation of new, smaller compounds (2,4-Diaminopteridine-6-carboxylic acid, N-(4-Aminobenzoyl)-L-glutamic acid, etc.) after drug degradation. The plasma-treated methotrexate solution also showed lower toxicity toward freshwater chlorella algae compared to the untreated solution. Finally, it can be said that non-thermal plasma jets are economically and environmentally friendly devices that have the potential to be used for the treatment of complex and resistive anticancer drug-polluted wastewaters.

11.
J Org Chem ; 88(14): 9686-9703, 2023 Jul 21.
Article in English | MEDLINE | ID: mdl-37437127

ABSTRACT

The In(OTf)3-catalyzed α-vinylation of various hydroxy-functionalized quaternary carbon centers using in situ generated isobutylene from tert-butyl acetate is presented as a novel synthetic methodology. Moreover, tert-butyl acetate is a nonflammable feed stock and is a readily available source for the in situ production of vinyl substituents, as demonstrated by the vinylation reaction with quaternary hydroxy/methoxy compounds. Moreover, an excellent selectivity for methylallylation over vinylation was obtained with Ni(OTf)2 as a catalyst. In the case of peroxyoxindole, methylallyl-functionalized 1,4-benzoxazin-3-one derivatives were formed through the sequential rearrangement of peroxyoxindole followed by the nucleophilic attack by isobutylene. The detailed mechanism for this reaction and rationalization for the selectivity are provided using kinetics and density functional theory studies.

12.
J Cell Biochem ; 124(9): 1289-1308, 2023 09.
Article in English | MEDLINE | ID: mdl-37450699

ABSTRACT

Modulation of autophagy is evolving as a relevant strategy in cancer pathogenesis and therapeutic intervention and hence, needs to be examined as a target for the promising anticancer agents. Fisetin, a dietary flavanol, is emerging as a potent anticancer agent, however, its tumour-specific pharmacological targets remain largely unexplored. This article describes correlative profiles of autophagy and apoptotic markers versus nuclear factor erythroid 2-related factor 2 (Nrf2) and reactive oxygen species (ROS) in the colorectal cancer (CRC) cell line SW-480. As compared to the untreated cells, significantly less number of fluorescent detected autophagic vacuoles (AVOs) in the fisetin-treated cells coincided with a similar decline of the autophagy flux markers, Beclin 1 and microtubule-associated protein-1 light chain-3 and accumulation of p62 in those cells. The significantly increased number of annexin-V/propidium iodide (+/+) positive and acridine orange/ethidium bromide-stained apoptotic cells coincided with the enhanced signals for the cleaved caspase 3 and nuclear PARP-1 in those fisetin-treated cells. This was consistent with the collapse of mitochondrial membrane potential and release of cytochrome c. The fisetin-treated cells showed increased ROS level and a significant decline in nuclear Nrf2 immunosignal versus recovery in nuclear Nrf2 due to the treatment with curcumin and resveratrol (Nrf2 activators) and thus, suggesting a role of Nrf2 suppression in fisetin-mediated apoptosis in SW-480 cells. The effect of chloroquine, an autophagy inhibitor, resulted into declined number of AVOs and enhanced apoptosis, similar to that of the fisetin effect. Also, regaining of AVOs number and reduced apoptosis of CRC cells due to the treatment with rapamycin, an autophagy inducer, could be observed. These loss and gain of functions experiments thus suggested a correlation between fisetin-mediated autophagy suppression and apoptotic induction in a colorectal cell line.


Subject(s)
Antineoplastic Agents , Colorectal Neoplasms , Humans , NF-E2-Related Factor 2/metabolism , Reactive Oxygen Species/metabolism , Cell Line, Tumor , Apoptosis , Antineoplastic Agents/pharmacology , Autophagy , Colorectal Neoplasms/drug therapy
14.
Am J Med Genet A ; 191(9): 2446-2450, 2023 09.
Article in English | MEDLINE | ID: mdl-37337918

ABSTRACT

Combined oxidative phosphorylation deficiency type 53 (COXPD53) is an autosomal recessive neurodevelopmental disorder (NDD) caused by homozygous variants in the gene C2orf69. Here, we report a novel frameshift variant c.187_191dupGCCGA, p.D64Efs*56 identified in an individual with clinical presentation of COXPD53 with developmental regression and autistic features. The variant c.187_191dupGCCGA, p.D64Efs*56 represents the most N-terminal part of C2orf69. Notable clinical features of COXPD53of the proband include developmental delay, developmental regression, seizures, microcephaly, and hypertonia. Structural brain defects of cerebral atrophy, cerebellar atrophy, hypomyelination, and thin corpus callosum were also observed. While we observe strong phenotypic overlap among affected individuals with C2orf69 variants, developmental regression and autistic features have not been previously described in individuals with COXPD53. Together, this case expands the genetic and clinical phenotypic spectrum of C2orf69-associated COXPD53.


Subject(s)
Autistic Disorder , Microcephaly , Nervous System Malformations , Humans , Microcephaly/genetics , Autistic Disorder/complications , Autistic Disorder/genetics , Seizures/genetics , Muscle Hypertonia , Atrophy
15.
FEBS Lett ; 597(13): 1702-1717, 2023 07.
Article in English | MEDLINE | ID: mdl-36971000

ABSTRACT

Upon heat shock, activated heat shock transcription factor 1 (HSF1) binds to the heat shock response elements (HSEs) in the promoters of mammalian heat shock protein (HSP)-encoding genes and recruits the preinitiation complex and coactivators, including Mediator. These transcriptional regulators may be concentrated in phase-separated condensates around the promoters, but they are too minute to be characterized in detail. We herein established HSF1-/- mouse embryonic fibroblasts harbouring HSP72-derived multiple HSE arrays and visualized the condensates of fluorescent protein-tagged HSF1 with liquid-like properties upon heat shock. Using this experimental system, we demonstrate that endogenous MED12, a subunit of Mediator, is concentrated in artificial HSF1 condensates upon heat shock. Furthermore, the knockdown of MED12 markedly reduces the size of condensates, suggesting an important role for MED12 in HSF1 condensate formation.


Subject(s)
DNA-Binding Proteins , Fibroblasts , Animals , Mice , Heat Shock Transcription Factors/genetics , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Fibroblasts/metabolism , Transcription Factors/metabolism , Heat-Shock Response/genetics , Mammals/metabolism
16.
Curr Stem Cell Res Ther ; 18(8): 1041-1055, 2023.
Article in English | MEDLINE | ID: mdl-36627778

ABSTRACT

Biomaterials are developed to aid a variety of regenerative medicine strategies, such as providing a framework for cell adhesion and proliferation or serving as carriers of bioactive factors, while stem cells are increasingly implanted in biomaterial scaffolds to improve therapeutic efficacy. Advanced biomaterials like metals, synthetic polymers, and ceramics are used in bone regeneration technology. The ultimate goal of biomaterial-directed SC (stem cells) culture is to replicate the physical and biochemical characteristics of the physiological SC niche. The primary structural component of tumour ECM (extracellular matrix) is collagen. Cancer initiation, EMT (epithelial-mesenchymal transition), drug resistance, and CSC (cancer stem cells) self-renewal have all been linked to collagen subtypes. The enhancement of liver CSCs has already been investigated using collagen I-based platforms. Alginate and chitosan are two naturally occurring polymers with biological macromolecules that are similar. Biomaterial-based therapies, on the whole, offer incredible versatility and tailorability in the fight against the disease. They could also be used as tissue-engineered scaffolds for immune cell replenishment, potentially making them a key weapon in the next generation of therapeutic approaches.


Subject(s)
Biocompatible Materials , Neoplasms , Humans , Biocompatible Materials/pharmacology , Tissue Scaffolds/chemistry , Collagen , Stem Cells , Neoplasms/therapy , Tissue Engineering
17.
J Org Chem ; 87(15): 9926-9939, 2022 08 05.
Article in English | MEDLINE | ID: mdl-35867027

ABSTRACT

Continuous-flow reactors provide an ideal tool for the synthesis of potentially explosive but synthetically useful organic substances like organic azides due to their intrinsically small volume leading to very effective collision and highly controlled reaction conditions. Herein, we report the continuous-flow direct azidation of various alcohols by using TMSN3 as an azide transfer reagent in the presence of Amberlyst-15 as a recyclable catalyst. Numerous 3-hydroxy-2-oxindoles effectively undergo azide transfer to afford azide-functionalized quaternary stereocenters in a continuous-flow module. Interestingly, peroxyoxindole undergoes sequential skeletal rearrangement to generate a carbocation followed by nucleophilic azidation to afford a library of substituted 2-azido-2H-benzo[b][1,4]oxazin-3(4H)-one derivatives under continuous flow. Furthermore, a continuous-flow Cu-catalyzed click reaction afforded triazole-functionalized deivatives. Next, reduction of azide in the presence of PPh3 affords the amine derivatives in good yields. The continuous-flow application was extended further for the thermolytic skeletal rearrangement of 3-azide-2-oxindole for the synthesis of biologically important quinoxalin-2(1H)-ones without any reagents. Furthermore, this continuous-flow direct azidation reaction is scaled up to 6.144 g of azides with a turnover number of 9.24 under safer conditions.


Subject(s)
Azides , Peroxides , Alcohols , Catalysis , Triazoles
18.
J Org Chem ; 86(13): 8805-8828, 2021 07 02.
Article in English | MEDLINE | ID: mdl-34151556

ABSTRACT

A base-free and acceptorless Ru-catalyzed dehydrogenative approach has been developed for the synthesis of N-heterocycles by using 1,3-dicarbonyls and amino alcohols through a domino sequential enamine formation and intramolecular oxidative cyclization strategy. This unified approach is also applicable for the synthesis of O-heterocycles involving 2-hydroxybenzyl alcohol as a coupling reactant via consecutive C-alkylation and intramolecular cyclization steps. The present protocol is general for the synthesis of varieties of biologically important scaffolds, such as tetrahydro-4H-indol-4-one, 3,4-dihydroacridin-1(2H)-one, and tetrahydro-1H-xanthen-1-ones derivatives using a single catalytic system, viz. RuH2CO(PPh3)3. Environmentally benign H2O and H2 are the only byproducts in this domino process. Moreover, RuH2CO(PPh3)3-catalyzed C3-alkylation of tetrahydro-4H-indol-4-one using alcohol as a alkylating partner is also described in this report. For the first time, a solvent-free gram-scale reaction for the acceptorless dehydrogenative annulation has been demonstrated. A plausible mechanism for the Ru-catalyzed base-free and acceptorless dehydrogenative annulation of amino alcohols or 2-hydroxybenzyl alcohols has been provided with several experimental investigations and spectroscopic evidence.


Subject(s)
Amino Alcohols , Alkylation , Catalysis , Cyclization
19.
Biology (Basel) ; 9(4)2020 Mar 28.
Article in English | MEDLINE | ID: mdl-32231097

ABSTRACT

Phylogenomics, the use of large datasets to examine phylogeny, has revolutionized the study of evolutionary relationships. However, genome-scale data have not been able to resolve all relationships in the tree of life; this could reflect, at least in part, the poor-fit of the models used to analyze heterogeneous datasets. Some of the heterogeneity may reflect the different patterns of selection on proteins based on their structures. To test that hypothesis, we developed a pipeline to divide phylogenomic protein datasets into subsets based on secondary structure and relative solvent accessibility. We then tested whether amino acids in different structural environments had distinct signals for the topology of the deepest branches in the metazoan tree. We focused on a dataset that appeared to have a mixture of signals and we found that the most striking difference in phylogenetic signal reflected relative solvent accessibility. Analyses of exposed sites (residues located on the surface of proteins) yielded a tree that placed ctenophores sister to all other animals whereas sites buried inside proteins yielded a tree with a sponge+ctenophore clade. These differences in phylogenetic signal were not ameliorated when we conducted analyses using a set of maximum-likelihood profile mixture models. These models are very similar to the Bayesian CAT model, which has been used in many analyses of deep metazoan phylogeny. In contrast, analyses conducted after recoding amino acids to limit the impact of deviations from compositional stationarity increased the congruence in the estimates of phylogeny for exposed and buried sites; after recoding amino acid trees estimated using the exposed and buried site both supported placement of ctenophores sister to all other animals. Although the central conclusion of our analyses is that sites in different structural environments yield distinct trees when analyzed using models of protein evolution, our amino acid recoding analyses also have implications for metazoan evolution. Specifically, our results add to the evidence that ctenophores are the sister group of all other animals and they further suggest that the placozoa+cnidaria clade found in some other studies deserves more attention. Taken as a whole, these results provide striking evidence that it is necessary to achieve a better understanding of the constraints due to protein structure to improve phylogenetic estimation.

20.
Dev Biol ; 461(1): 19-30, 2020 05 01.
Article in English | MEDLINE | ID: mdl-31911183

ABSTRACT

Rab11, a member of Rab-GTPase family, and a marker of recycling endosomes has been reported to be involved in the differentiation of various tissues in Drosophila. Here we report a novel role of Rab11 in the differentiation of stellate cells via the non-canonical Notch pathway in Malpighian tubules. During Malpighian tubule development caudal visceral mesodermal cells intercalate into the epithelial tubule of ectodermal origin consisting of principal cells, undergo mesenchymal to epithelial transition and differentiate into star shaped stellate cells in adult Malpighian tubule. Two transcription factors, Teashirt and Cut (antagonistic to each other) are known to be expressed in stellate cells and principal cells, respectively, from early stages of development and serve as markers for these cells. Inhibition of Rab11 function or over-expression of activated Notch in stellate cells resulted in the expression of Cut that leads to down-regulation of Teashirt or vice-versa that leads to hampered differentiation of stellate cells. The stellate cells do not transform to star/bar shaped and remain in mesenchymal state in adult Malpighian tubule. Over-expression of Deltex, which plays important role in non-canonical Notch signaling pathway, shows similar phenotype of stellate cells as seen in individuals with down-regulated Rab11, while down-regulation of Deltex in genetic background of Rab11RNAi rescues Teashirt expression and shape of stellate cells. Our experiments suggest that an inhibition or reduction of Rab11 function in stellate cells results in the faulty recycling of Notch receptors to plasma membrane as they accumulate in early and late endosomes, leading to Deltex mediated non-canonical Notch activation.


Subject(s)
Drosophila Proteins/metabolism , Drosophila melanogaster/embryology , Malpighian Tubules/embryology , Organogenesis/physiology , Receptors, Notch/metabolism , rab GTP-Binding Proteins/metabolism , Animals , Cell Differentiation/genetics , Cell Membrane/metabolism , Drosophila Proteins/genetics , Drosophila melanogaster/genetics , Embryo, Nonmammalian/embryology , Homeodomain Proteins/metabolism , Malpighian Tubules/metabolism , Membrane Proteins/metabolism , Mesoderm/cytology , Nuclear Proteins/metabolism , Organogenesis/genetics , RNA Interference , RNA, Small Interfering/genetics , Repressor Proteins/metabolism , Signal Transduction/physiology , Transcription Factors/metabolism , rab GTP-Binding Proteins/genetics
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